Question

Which expression has an estimated product of 45?

44.7x2.1
7.5x84
8.7x5.28
38.1 x 7.3​

Answer 1

8.7 × 5.28 has an estimated product of 45.

Explanation:

44.7 × 2.1 doesn't work because 44.7 is nearly 45 by itself, so doubling it wouldn't work.

7.5 × 84 doesn't work either because 84 is way past 45, so it can't work.

38.1 × 7.3 also doesn't work because 38 multiplied by 7 couldn't get anywhere near 45.

Answer 2

Answer: 8.7 x 5.28

We have to find that expression , which has an estimated product of

1.→44.7 x 2.1

2.→7.5 x 8.4

3.→8.7 x 5.28

4.→38.1 x 7.3

We will start from option 1.

→44.7 x 2.1

44.7 when estimated to nearest tenth=45

2.1, when estimated to nearest tenth=2

44.7 × 2.1=45×2=90

Option 2

7.5 x 8.4

7.5 when estimated to nearest tenth=8

8.4, when estimated to nearest tenth=8

⇒7.5 × 8.4=8×8=64

Option 3

8.7 × 5.28

8.7, when estimated to nearest tenth=9

5.28, when estimated to nearest tenth=5

⇒8.7 × 5.28=9×5=45

Option D

38.1 × 7.3

38.1 when estimated to nearest tenth=38

7.3, when estimated to nearest tenth=7

⇒38×7=266

Option C:⇒8.7 × 5.28 has an estimated product of 45